Write your own dispatcher (Get an idea about the CustomURIBasedDispatcher.java )
https://svn.wso2.com/wso2/custom/projects/projects/carbon/3.2.3/trunk/dependencies/synapse/2.1.0-wso2v5/modules/core/src/main/java/org/apache/synapse/core/axis2/CustomURIBasedDispatcher.java

Copy it to
[WSO2_ESB_Installation]/repository/components/lib and restart ESB.

Include the following in the axis2.xml. It should be inserted into the dispatch phase of the In-Flow of the ESB. It should be the first handler in the Dispatch phase.